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channel_layout.h
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1 /*
2  * Copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
3  * Copyright (c) 2008 Peter Ross
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #ifndef AVUTIL_CHANNEL_LAYOUT_H
23 #define AVUTIL_CHANNEL_LAYOUT_H
24 
25 #include <stdint.h>
26 
27 /**
28  * @file
29  * audio channel layout utility functions
30  */
31 
32 /**
33  * @addtogroup lavu_audio
34  * @{
35  */
36 
37 /**
38  * @defgroup channel_masks Audio channel masks
39  *
40  * A channel layout is a 64-bits integer with a bit set for every channel.
41  * The number of bits set must be equal to the number of channels.
42  * The value 0 means that the channel layout is not known.
43  * @note this data structure is not powerful enough to handle channels
44  * combinations that have the same channel multiple times, such as
45  * dual-mono.
46  *
47  * @{
48  */
49 #define AV_CH_FRONT_LEFT 0x00000001
50 #define AV_CH_FRONT_RIGHT 0x00000002
51 #define AV_CH_FRONT_CENTER 0x00000004
52 #define AV_CH_LOW_FREQUENCY 0x00000008
53 #define AV_CH_BACK_LEFT 0x00000010
54 #define AV_CH_BACK_RIGHT 0x00000020
55 #define AV_CH_FRONT_LEFT_OF_CENTER 0x00000040
56 #define AV_CH_FRONT_RIGHT_OF_CENTER 0x00000080
57 #define AV_CH_BACK_CENTER 0x00000100
58 #define AV_CH_SIDE_LEFT 0x00000200
59 #define AV_CH_SIDE_RIGHT 0x00000400
60 #define AV_CH_TOP_CENTER 0x00000800
61 #define AV_CH_TOP_FRONT_LEFT 0x00001000
62 #define AV_CH_TOP_FRONT_CENTER 0x00002000
63 #define AV_CH_TOP_FRONT_RIGHT 0x00004000
64 #define AV_CH_TOP_BACK_LEFT 0x00008000
65 #define AV_CH_TOP_BACK_CENTER 0x00010000
66 #define AV_CH_TOP_BACK_RIGHT 0x00020000
67 #define AV_CH_STEREO_LEFT 0x20000000 ///< Stereo downmix.
68 #define AV_CH_STEREO_RIGHT 0x40000000 ///< See AV_CH_STEREO_LEFT.
69 #define AV_CH_WIDE_LEFT 0x0000000080000000ULL
70 #define AV_CH_WIDE_RIGHT 0x0000000100000000ULL
71 #define AV_CH_SURROUND_DIRECT_LEFT 0x0000000200000000ULL
72 #define AV_CH_SURROUND_DIRECT_RIGHT 0x0000000400000000ULL
73 #define AV_CH_LOW_FREQUENCY_2 0x0000000800000000ULL
74 
75 /** Channel mask value used for AVCodecContext.request_channel_layout
76  to indicate that the user requests the channel order of the decoder output
77  to be the native codec channel order. */
78 #define AV_CH_LAYOUT_NATIVE 0x8000000000000000ULL
79 
80 /**
81  * @}
82  * @defgroup channel_mask_c Audio channel convenience macros
83  * @{
84  * */
85 #define AV_CH_LAYOUT_MONO (AV_CH_FRONT_CENTER)
86 #define AV_CH_LAYOUT_STEREO (AV_CH_FRONT_LEFT|AV_CH_FRONT_RIGHT)
87 #define AV_CH_LAYOUT_2POINT1 (AV_CH_LAYOUT_STEREO|AV_CH_LOW_FREQUENCY)
88 #define AV_CH_LAYOUT_2_1 (AV_CH_LAYOUT_STEREO|AV_CH_BACK_CENTER)
89 #define AV_CH_LAYOUT_SURROUND (AV_CH_LAYOUT_STEREO|AV_CH_FRONT_CENTER)
90 #define AV_CH_LAYOUT_3POINT1 (AV_CH_LAYOUT_SURROUND|AV_CH_LOW_FREQUENCY)
91 #define AV_CH_LAYOUT_4POINT0 (AV_CH_LAYOUT_SURROUND|AV_CH_BACK_CENTER)
92 #define AV_CH_LAYOUT_4POINT1 (AV_CH_LAYOUT_4POINT0|AV_CH_LOW_FREQUENCY)
93 #define AV_CH_LAYOUT_2_2 (AV_CH_LAYOUT_STEREO|AV_CH_SIDE_LEFT|AV_CH_SIDE_RIGHT)
94 #define AV_CH_LAYOUT_QUAD (AV_CH_LAYOUT_STEREO|AV_CH_BACK_LEFT|AV_CH_BACK_RIGHT)
95 #define AV_CH_LAYOUT_5POINT0 (AV_CH_LAYOUT_SURROUND|AV_CH_SIDE_LEFT|AV_CH_SIDE_RIGHT)
96 #define AV_CH_LAYOUT_5POINT1 (AV_CH_LAYOUT_5POINT0|AV_CH_LOW_FREQUENCY)
97 #define AV_CH_LAYOUT_5POINT0_BACK (AV_CH_LAYOUT_SURROUND|AV_CH_BACK_LEFT|AV_CH_BACK_RIGHT)
98 #define AV_CH_LAYOUT_5POINT1_BACK (AV_CH_LAYOUT_5POINT0_BACK|AV_CH_LOW_FREQUENCY)
99 #define AV_CH_LAYOUT_6POINT0 (AV_CH_LAYOUT_5POINT0|AV_CH_BACK_CENTER)
100 #define AV_CH_LAYOUT_6POINT0_FRONT (AV_CH_LAYOUT_2_2|AV_CH_FRONT_LEFT_OF_CENTER|AV_CH_FRONT_RIGHT_OF_CENTER)
101 #define AV_CH_LAYOUT_HEXAGONAL (AV_CH_LAYOUT_5POINT0_BACK|AV_CH_BACK_CENTER)
102 #define AV_CH_LAYOUT_6POINT1 (AV_CH_LAYOUT_5POINT1|AV_CH_BACK_CENTER)
103 #define AV_CH_LAYOUT_6POINT1_BACK (AV_CH_LAYOUT_5POINT1_BACK|AV_CH_BACK_CENTER)
104 #define AV_CH_LAYOUT_6POINT1_FRONT (AV_CH_LAYOUT_6POINT0_FRONT|AV_CH_LOW_FREQUENCY)
105 #define AV_CH_LAYOUT_7POINT0 (AV_CH_LAYOUT_5POINT0|AV_CH_BACK_LEFT|AV_CH_BACK_RIGHT)
106 #define AV_CH_LAYOUT_7POINT0_FRONT (AV_CH_LAYOUT_5POINT0|AV_CH_FRONT_LEFT_OF_CENTER|AV_CH_FRONT_RIGHT_OF_CENTER)
107 #define AV_CH_LAYOUT_7POINT1 (AV_CH_LAYOUT_5POINT1|AV_CH_BACK_LEFT|AV_CH_BACK_RIGHT)
108 #define AV_CH_LAYOUT_7POINT1_WIDE (AV_CH_LAYOUT_5POINT1|AV_CH_FRONT_LEFT_OF_CENTER|AV_CH_FRONT_RIGHT_OF_CENTER)
109 #define AV_CH_LAYOUT_7POINT1_WIDE_BACK (AV_CH_LAYOUT_5POINT1_BACK|AV_CH_FRONT_LEFT_OF_CENTER|AV_CH_FRONT_RIGHT_OF_CENTER)
110 #define AV_CH_LAYOUT_OCTAGONAL (AV_CH_LAYOUT_5POINT0|AV_CH_BACK_LEFT|AV_CH_BACK_CENTER|AV_CH_BACK_RIGHT)
111 #define AV_CH_LAYOUT_STEREO_DOWNMIX (AV_CH_STEREO_LEFT|AV_CH_STEREO_RIGHT)
112 
113 enum AVMatrixEncoding {
114  AV_MATRIX_ENCODING_NONE,
115  AV_MATRIX_ENCODING_DOLBY,
116  AV_MATRIX_ENCODING_DPLII,
117  AV_MATRIX_ENCODING_DPLIIX,
118  AV_MATRIX_ENCODING_DPLIIZ,
119  AV_MATRIX_ENCODING_DOLBYEX,
120  AV_MATRIX_ENCODING_DOLBYHEADPHONE,
121  AV_MATRIX_ENCODING_NB
122 };
123 
124 /**
125  * @}
126  */
127 
128 /**
129  * Return a channel layout id that matches name, or 0 if no match is found.
130  *
131  * name can be one or several of the following notations,
132  * separated by '+' or '|':
133  * - the name of an usual channel layout (mono, stereo, 4.0, quad, 5.0,
134  * 5.0(side), 5.1, 5.1(side), 7.1, 7.1(wide), downmix);
135  * - the name of a single channel (FL, FR, FC, LFE, BL, BR, FLC, FRC, BC,
136  * SL, SR, TC, TFL, TFC, TFR, TBL, TBC, TBR, DL, DR);
137  * - a number of channels, in decimal, optionally followed by 'c', yielding
138  * the default channel layout for that number of channels (@see
139  * av_get_default_channel_layout);
140  * - a channel layout mask, in hexadecimal starting with "0x" (see the
141  * AV_CH_* macros).
142  *
143  * @warning Starting from the next major bump the trailing character
144  * 'c' to specify a number of channels will be required, while a
145  * channel layout mask could also be specified as a decimal number
146  * (if and only if not followed by "c").
147  *
148  * Example: "stereo+FC" = "2c+FC" = "2c+1c" = "0x7"
149  */
150 uint64_t av_get_channel_layout(const char *name);
151 
152 /**
153  * Return a description of a channel layout.
154  * If nb_channels is <= 0, it is guessed from the channel_layout.
155  *
156  * @param buf put here the string containing the channel layout
157  * @param buf_size size in bytes of the buffer
158  */
159 void av_get_channel_layout_string(char *buf, int buf_size, int nb_channels, uint64_t channel_layout);
160 
161 struct AVBPrint;
162 /**
163  * Append a description of a channel layout to a bprint buffer.
164  */
165 void av_bprint_channel_layout(struct AVBPrint *bp, int nb_channels, uint64_t channel_layout);
166 
167 /**
168  * Return the number of channels in the channel layout.
169  */
170 int av_get_channel_layout_nb_channels(uint64_t channel_layout);
171 
172 /**
173  * Return default channel layout for a given number of channels.
174  */
175 int64_t av_get_default_channel_layout(int nb_channels);
176 
177 /**
178  * Get the index of a channel in channel_layout.
179  *
180  * @param channel a channel layout describing exactly one channel which must be
181  * present in channel_layout.
182  *
183  * @return index of channel in channel_layout on success, a negative AVERROR
184  * on error.
185  */
186 int av_get_channel_layout_channel_index(uint64_t channel_layout,
187  uint64_t channel);
188 
189 /**
190  * Get the channel with the given index in channel_layout.
191  */
192 uint64_t av_channel_layout_extract_channel(uint64_t channel_layout, int index);
193 
194 /**
195  * Get the name of a given channel.
196  *
197  * @return channel name on success, NULL on error.
198  */
199 const char *av_get_channel_name(uint64_t channel);
200 
201 /**
202  * Get the description of a given channel.
203  *
204  * @param channel a channel layout with a single channel
205  * @return channel description on success, NULL on error
206  */
207 const char *av_get_channel_description(uint64_t channel);
208 
209 /**
210  * Get the value and name of a standard channel layout.
211  *
212  * @param[in] index index in an internal list, starting at 0
213  * @param[out] layout channel layout mask
214  * @param[out] name name of the layout
215  * @return 0 if the layout exists,
216  * <0 if index is beyond the limits
217  */
218 int av_get_standard_channel_layout(unsigned index, uint64_t *layout,
219  const char **name);
220 
221 /**
222  * @}
223  */
224 
225 #endif /* AVUTIL_CHANNEL_LAYOUT_H */
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